*next take at setting up a dma mask by default for platform devices@ 2019-08-11 8:05 Christoph Hellwig
2019-08-11 8:05 ` [PATCH 1/6] usb: don't create dma pools for HCDs with a localmem_pool Christoph Hellwig
` (6 more replies)0 siblings, 7 replies; 18+ messages in thread
From: Christoph Hellwig @ 2019-08-11 8:05 UTC (permalink / raw)
To: Greg Kroah-Hartman, Maxime Chevallier
Cc: Gavin Li, Laurentiu Tudor, Minas Harutyunyan, Alan Stern,
Geoff Levand, Michal Simek, Shawn Guo, Sascha Hauer,
Pengutronix Kernel Team, Fabio Estevam, NXP Linux Team,
Olav Kongas, Tony Prisk, Mathias Nyman, Bin Liu,
linux-arm-kernel, linux-usb, linuxppc-dev, iommu, linux-arch,
linux-kernel
Hi all,
this is another attempt to make sure the dma_mask pointer is always
initialized for platform devices. Not doing so lead to lots of
boilerplate code, and makes platform devices different from all our
major busses like PCI where we always set up a dma_mask. In the long
run this should also help to eventually make dma_mask a scalar value
instead of a pointer and remove even more cruft.
The bigger blocker for this last time was the fact that the usb
subsystem uses the presence or lack of a dma_mask to check if the core
should do dma mapping for the driver, which is highly unusual. So we
fix this first. Note that this has some overlap with the pending
desire to use the proper dma_mmap_coherent helper for mapping usb
buffers. The first two patches from this series should probably
go into 5.3 and then uses as the basis for the decision to use
dma_mmap_coherent.
^permalinkrawreply [flat|nested] 18+ messages in thread

*Re: next take at setting up a dma mask by default for platform devices
2019-08-11 8:05 next take at setting up a dma mask by default for platform devices Christoph Hellwig
` (5 preceding siblings ...)
2019-08-11 8:05 ` [PATCH 6/6] driver core: initialize a default DMA mask for platform device Christoph Hellwig
@ 2019-08-15 13:23 ` Greg Kroah-Hartman
2019-08-15 13:25 ` Christoph Hellwig6 siblings, 1 reply; 18+ messages in thread
From: Greg Kroah-Hartman @ 2019-08-15 13:23 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Maxime Chevallier, Gavin Li, Laurentiu Tudor, Minas Harutyunyan,
Alan Stern, Geoff Levand, Michal Simek, Shawn Guo, Sascha Hauer,
Pengutronix Kernel Team, Fabio Estevam, NXP Linux Team,
Olav Kongas, Tony Prisk, Mathias Nyman, Bin Liu,
linux-arm-kernel, linux-usb, linuxppc-dev, iommu, linux-arch,
linux-kernel
On Sun, Aug 11, 2019 at 10:05:14AM +0200, Christoph Hellwig wrote:
> Hi all,
>
> this is another attempt to make sure the dma_mask pointer is always
> initialized for platform devices. Not doing so lead to lots of
> boilerplate code, and makes platform devices different from all our
> major busses like PCI where we always set up a dma_mask. In the long
> run this should also help to eventually make dma_mask a scalar value
> instead of a pointer and remove even more cruft.
>
> The bigger blocker for this last time was the fact that the usb
> subsystem uses the presence or lack of a dma_mask to check if the core
> should do dma mapping for the driver, which is highly unusual. So we
> fix this first. Note that this has some overlap with the pending
> desire to use the proper dma_mmap_coherent helper for mapping usb
> buffers. The first two patches from this series should probably
> go into 5.3 and then uses as the basis for the decision to use
> dma_mmap_coherent.
I've taken the first 2 patches for 5.3-final. Given that patch 3 needs
to be fixed, I'll wait for a respin of these before considering them.
thanks,
greg k-h
^permalinkrawreply [flat|nested] 18+ messages in thread